See, that's the thing. Path G is not available on Tyson's route.
Yep there is one medal that is very difficult to find:
(Spoiler: you ruin your own acomplishment finding it yourself, if you take a peak.)
Gemini: Route Tyson - Path B!!
It shouldn't just be there. Though the flag has been adjusted slightly, and a replay of that Path to troubleshoot, should fix it.
Grizz edited Path B a bit so you might need to replay that in order for it to register Gemini.
There's a Path G??